targhooks.c (default_stack_protect_guard): Avoid sharing RTL for __stack_chk_guard.

	* targhooks.c (default_stack_protect_guard): Avoid sharing RTL
	for __stack_chk_guard.

	* gcc.target/m68k/20100512-1.c: New.

From-SVN: r159310

gcc/ChangeLog

+2010-05-12  Maxim Kuvyrkov  <maxim@codesourcery.com>
+
+	* targhooks.c (default_stack_protect_guard): Avoid sharing RTL
+	for __stack_chk_guard.
+
 2010-05-11  Jakub Jelinek  <jakub@redhat.com>
 
 	* c-opts.c (c_common_parse_file): If start_end_main_source_file,

gcc/targhooks.c

@@ -499,6 +499,8 @@ default_stack_protect_guard (void)
 
   if (t == NULL)
     {
+      rtx x;
+
       t = build_decl (UNKNOWN_LOCATION,
 		      VAR_DECL, get_identifier ("__stack_chk_guard"),
 		      ptr_type_node);
@@ -510,6 +512,11 @@ default_stack_protect_guard (void)
       DECL_ARTIFICIAL (t) = 1;
       DECL_IGNORED_P (t) = 1;
 
+      /* Do not share RTL as the declaration is visible outside of
+	 current function.  */
+      x = DECL_RTL (t);
+      RTX_FLAG (x, used) = 1;
+
       stack_chk_guard_decl = t;
     }
 

gcc/testsuite/ChangeLog

+2010-05-12  Maxim Kuvyrkov  <maxim@codesourcery.com>
+
+	* gcc.target/m68k/20100512-1.c: New.
+
 2010-05-12  Eric Botcazou  <ebotcazou@adacore.com>
 
 	* gnat.dg/lto8.adb: New test.

gcc/testsuite/gcc.target/m68k/20100512-1.c

+/* { dg-do compile } */
+/* { dg-options "-O2 -fstack-protector" } */
+/* { dg-require-effective-target fstack_protector } */
+/* There should be 2 references to __stack_chk_guard in every function.  */
+/* { dg-final { scan-assembler-times "__stack_chk_guard" 4 } } */
+
+#include <stdlib.h>
+#include <string.h>
+void doTest1(void) {
+  volatile char foo[10];
+  memset((void *)foo, 1, 100);
+}
+void doTest2(void) {
+  volatile char foo[10];
+  memset((void *)foo, 1, 100);
+}